A 3d printed knob for sma connectors

Sourced a bunch of 3d printed knobs for sna fittings.  I found it a bit of a pain to turn the fitting and these knobs fit right onto the fitting via a friction fit.  There are other designs that have a catch in them to hold on to the backside of the fitting, but these seem to work just fine.

For another run I would reduce the outside diameter. Using sma cables to link up pcb boards, the smaller size would offer better clearance to the mounting board for the pcbs.

New Toys to Play With

Finally I’ve been able to get some shack time.  It’s been a little busy with the household chores but now that list is down to a reasonable level, time for some bench work.

The trip to Dayton and FDIM was very rewarding.  Picked up my Siglent Spectrum Analyzer, IOT kit from Kanga, attenuators, test cables, and a few books.

Putting the IOT kit together went smoothly, or so I thought. Everything went smoothly as far as establishing a WiFi connection and communicating to the board with my phone. Frequency changes appeared to be working well but, I was getting a very poor signal output.  As I checked things out, I thought I blew the output port somehow as the signal now was completely lost.  So I wired up the B output port to a header and in the process of that I was getting intermittent output on that port and then the 1^st port began to work.  Closer examination of the dds chip revealed that the pins in the output area were slightly offset from the pads. So a little solder and heat with a touch up from solder wick seems to have cured the problem.  Take a look at the upper right corner of the chip in the picture.

Not sure exactly where I’m headed with this project, but at the moment it’s a learning exercise for something down the road. I find it interesting to be able to control something from a phone or computer via WiFi.

As well I’m working on getting ready for portable hf operating.  Rig is ready to go but antenna I’ve just started to work on.  I bought a no tune end fed half wave antenna kit from qrpguys that is almost ready to try out.  Just need to source some #22 or #24 wire and make a couple of insulators.

Between all that I’m trying to learn how to use the Spectrum Analyzer.  Great addition to the bench.  So far I've just been observing the signal output of dds chips and the IOT board output.  One other thing I tried out is connecting a 40meter BPF to the tracking generator and the SA input.  The ability to adjust the filter in real time is a really nice feature. I'm now thinking about using the SA on the LBS project I built a couple of years ago. Should prove to be interesting checking out that rig.

73, Peter